Actually php says:
Warning: Compilation failed: two named subpatterns have the same name at
offset 679
The message is not helpful to find the duplicate name inside the
MagicWordArray, because the generated regex is unknown to count the
correct offset.
Try to detect such duplicates and throw an exception with more
information and a stacktrace.
Change-Id: I95dea67da06aa4000d52ac3338c3b865450b3e23
